<template>
  <section class="p-10">
    <el-tree
      :data="data"
      ref="vuetree"
      :props="defaultProps"
      :expand-on-click-node="false"
      @node-click="handleNodeClick"
      @check-change="handleCheckChange" 
       :default-expanded-keys="defaultExpend" 
      highlight-current
      show-checkbox
      node-key="id"
      default-expand-all
    />
  </section>
</template>
<script>
export default {
  data() {
    return {
      selectList:[] ,
      defaultExpend:[0],
      data: [
        {
          id: 1,
          label: "一级 1",
          children: [
            {
              id: 4,
              label: "二级 1-1",
              children: [
                {
                  id: 9,
                  label: "三级 1-1-1"
                },
                {
                  id: 10,
                  label: "三级 1-1-2"
                }
              ]
            }
          ]
        },
        {
          id: 2,
          label: "一级 2",
          children: [
            {
              id: 5,
              label: "二级 2-1"
            },
            {
              id: 6,
              label: "二级 2-2"
            }
          ]
        },
        {
          id: 3,
          label: "一级 3",
          children: [
            {
              id: 7,
              label: "二级 3-1"
            },
            {
              id: 8,
              label: "二级 3-2"
            }
          ]
        }
      ],
      defaultProps: {
        children: "children",
        label: "label"
      }
    };
  },
  methods: {
    handleNodeClick(data) {
      console.log(data);
    },
    handleCheckChange(data){
        console.log(data)
        this.selectList.push(data.id)
    }
  },
  mounted() {
    this.$nextTick(function() {
      this.$refs["vuetree"].setCurrentKey(10);
      this.$refs["vuetree"].setCheckedKeys([3,10])
    });
  }
};
</script>
